# Problem.
This problem is about the random value.
# How To Solve.
First, Connect the server ssh random@pwnable.kr -p2222
and I check the source code about the random.
According to the code, The core of the program is the XOR operation of key & random value. If the computed value is equal to 0xdeadbeef, we can see the flag.
Because of the large number of cases, I analyzed the random program using the GDB.
The results of the analysis are as follows.
I used the following method to find the key value by inverse operation of 0xdeadbeef and random value.
Since the random value is in [rbp-0x4], So I put the breakpoint in the next line <+21> and run the program. And I checked the value in [rbp-0x4].
Finally, The key value could be obtained by XOR operation with 0xdeadbeef & 0x6b8b4567.
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